1. Field of the Invention
This invention concerns an automatic fastening and alarming circuit for a vehicle seat belt, and more particularly relates to an improved automatic fastening and alarming circuit for a vehicle seat belt wherein the seat belt is previously laid on a seat for fastening to a rider sitting thereon.
2. Prior Art
It is well known that the use of a seat belt can provide effective protection for the driver of a vehicle against collision or other accidents and various improvements have been proposed for seat belt devices. The driver, however, often leaves the seat belt unfastened during operation of the vehicle because of the difficulties in fastening and unfastening the seat belt, which sometimes fails to provide sufficient protection for the driver against the accident.
Improved seat belt devices capable of automatically fastening a seat belt to a driver or other riders in a vehicle have been proposed, including the well-known preferred device as disclosed in Japanese Laid-open Patent Specificationn No. 49,128/73. In the above device disclosed, a seat belt previously extends over a seat and is usually fixed to a car body at one end and to a door at the other end. The rider can sit on the seat in this state while the seat belt is retained at its intermediate portion by a latch provided in front of the seat. When the driver sits on the seat for driving the car, the seat belt is automatically released from the retention by the latch and fastened to the driver.
An object of this invention is to provide an improved automatic fastening and alarming circuit capable of automatically fastening a seat belt positively to a rider upon sitting on the seat, as well as warning him of a state where the seat belt is not fastened or is unfastened by the rider after once being fastened.